Contact breaker assemblies with improved contact breaker arm retaining means

ABSTRACT

A subassembly for use in the manufacture of a contact breaker assembly for an ignition distributor includes an insulating heel member having a pair of oppositely directed shoulders. A conductive shell member is engaged with the heel member the shell member being of generally U-shaped cross section and the heel member being received between the limbs of the shell member. The shoulders of the heel member engage opposite ends of the shell member so as to resist longitudinal movement of the shell member relative to the heel member, and one of the limbs of the shell member includes a barb which bites into one of the shoulders of the heel member to resist disengagement of the shell member from the heel member in a direction parallel to the limbs of the shell member. In use the shell member carries the movable contact of the contact breaker assembly.

United States Patent [73] Assignee Joseph Lucasflndustries) Limited Birmingham, England [32] Priority Nov. 22, 1968 [33] Great Britain 55,520/68 [54] CONTACT BREAKER ASSEMBLIES WITH IMPROVED CONTACT BREAKER ARM RETAlNlNG MEANS 2 Claims, 2 Drawing Figs.

[52] U.S.Cl 200/19 R, 200/30, 200/31, 200/!66 CT [51] lnt.Cl ..H0lh19/00, HOlh 3/00 [50] Field of Search 200/19-32, 166 CT [56] References Cited UNITED STATES PATENTS 3,003,043 10/ l 961 Meyer, Jr. et a]. 200/30 3,370,l36 2/1968 Neely .1 200/19 3.499.128 3/1970 1. 200/30 x 3,509.294 4/1970 200/22 3,5l0,609 5/1970 200/31 x Primary Examiner-J. R. Scott Attorney-Holman & Stern ABSTRACT: A subassembly for use in the manufacture of a contact breaker assembly for an ignition distributor includes an insulating heel member having a pair of oppositely directed shoulders. A conductive shell member is engaged with the heel member the shell member being of generally Ushapcd cross section and the heel member being received between the limbs of the shell member. The shoulders of the heel member engage opposite ends of the shell member so as to resist Ion gitudinal movement of the shell member relative to the heel member, and one of the limbs of the shell member includes a barb which bites into one of the shoulders of the heel member to resist disengagement of the shell member from the heel member in a direction parallel to the limbs of the shell member. in use the shell member carries the movable contact of the contact breaker assembly.

PATENTEU DECZI L97! 3629-527 INVENTOE MW BY,

AT TaN as CONTACT BREAKER ASSEMBLIES WITH IMPROVED CONTACT BREAKER ARM RETAINING MEANS BACKGROUND OF THE INVENTION This invention relates to contact breaker heel subassemblies for use in the manufacture of contact breaker assemblies for ignition distributors, of the kind including an insulating heel member which in use is engaged by the cam of an ignition distributor, with the heel member supporting a conductive shell which carries the movable contact of the contact breaker assembly.

SUMMARY OF THE INVENTION A subassembly according to the invention includes an insulating heel member having a pair of oppositely directed shoulders thereon, and a conductive shell member engaged with the heel member, said shell member being of generally U-shaped cross section and said heel member being received between the limbs of said shell member, said shoulders of said heel member engaging opposite ends of said shell member and thereby resisting longitudinal movement of the shell member relative to the heel member and one of the limbs of said shell member including an integral protrusion which bites into one of said shoulders and thereby resists movement of the shell member relative to the heel member in a direction parallel to the limbs of the shell member.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings FIG. 1 is an exploded perspective view, not to scale, of a subassembly, for use in a contact breaker assembly, according to one example of the invention, and,

FIG. 2 is a plan view of a contact breaker assembly incorporating the subassembly shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, the subassembly includes a moulded synthetic resin heel member 11 including a central portion 12 of generally rectangular cross section. Integral with the portion 12, at one end thereof is a cam follower portion 13, and integral with the portion 12 at the end thereof remote from the cam follower portion 13 is a pair of curved, resilient arms 14 which defined between them a passage 15. One of the arms 14, defines a first outwardly directed shoulder 16 with the portion 12, and a second outwardly directed shoulder 17 is defined with the portion 12, by the portion 13.

A conductive shell member 18 is engaged with the heel member 11. The shell member 18 is formed from steel sheet, and is generally of U-shaped cross section, having a base portion 19 and a pair of parallel limbs 21,22. The limb 21 of the shell member 18 is extended at one end to define an arm 23 which carries a contact piece 24, and the limb 22 is formed at i one end with an integral barb like protrusion 25. The shell member 18 is engaged with the heel 11 by inserting the por tion 12 of the heel 11 between the limbs 21,22 of the shell member 18. The dimensions of the shell member 18 are such that when the shell member 18 and the heel 11 are interengaged, then the end of the limb 21, remote from the arm 23, engages the shoulder 16, while the end of the limb 22 carrying the protrusion 25 engages the shoulder 17. The shoulders 16,17 resist movement of the shell member relative to the heel member in a longitudinal direction, and the barb 25 bites into the shoulder 17, and thereby resists movement of the shell member 18 relative to the heel member 11 in a direction parallel to the limbs 21,22.

During the manufacture of a contact breaker assembly, the subassembly constituted by the heel member 11 and the shell member 18 is passed on to a riveting station wherein the shell member 18 is riveted to the heel member 11, with the rivet passing through the limbs 21, 22 of the shell member 18 and through the portion 12 of the heel member 11. The rivet also passes through one end of a conductive leaf spring, to secure the leaf spring to the subassembly.

As shown in FIG. 2, the heel assembly so formed is then mounted on a contact plate 26. The contact plate 26 includes an integral, upstanding tag 27 carrying a further contact piece 28, aperture 30, and an upstanding post 29 which extends through the bore 15 so that the heel assembly is pivotally mounted on the contact plate 26. The other end of said conductive leaf spring is anchored to the plate, and the spring urges the heel assembly to pivot relative to the plate to engage the contact piece 24 with the further contact piece 28 carried by the upstanding tag 27.

In use the contact breaker assembly is mounted in an ignition distributor, and the cam follower portion 13 of the heel member 11 is intermittently engaged by the lobes of the cam shaft of the distributor. Engagement of the lobes of the cam shaft of the distributor with the portion 13 of the heel member 11 serves to cause the heel assembly to pivot relative to the contact breaker plate 26 to move the movable contact, constituted by the contact piece 24, of the contact breaker assembly into and out of engagement with the fixed contact, constituted by the further contact piece 28 of the contact breaker assembly.

It will be appreciated, that the protrusion 25 on the limb 22 of the shell member 18 serves to minimize the risk of disengagement of the shell member 18 from the heel member 11 during the stage in the manufacture of the contact breaker assembly between the station wherein the shell member is assembled to the heel member, and the riveting station.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A contact breaker heel subassembly including an insulating heel member having a pair of oppositely directed shoulders thereon, and a conductive shell member engaged with the heel member, said shell member being of generally U-shaped cross section and said heel member being received between the limbs of said shell member, said shoulders of said heel member engaging opposite ends of said shell member and thereby resisting longitudinal movement of the shell member relative to the heel member and one of the limbs of said shell member including an integral protrusion which bites into one of said shoulders and thereby resists movement of the shell member relative to the heel member in a direction parallel to the limbs of the shell member.

2. A contact breaker assembly for ignition distributors including a contact plate, an upstanding part on the plate, a contact piece on the upstanding part defining a fixed control a post on the plate in spaced relationship to the upstanding part, an insulating heel member, said heel member having at one end a pair of curved resilient arms forming therebetween a passage and at the other end a cam follower portion, one of said arms defining with the heel member a first outwardly directed shoulder, said cam follower defining with said heel member a second outwardly directed shoulder, a generally U- shaped conductive shell member engaged with the heel member, with the heel member being received between the limbs of the shell member, said first and second shoulders engaging opposite ends of the shell member thereby resisting longitudinal movement of the shell member relative to the heel member, one of the limbs of the shell member having an integral protrusion which bites into one of said shoulders for resisting movement of the shell member relative to the heel member in a direction parallel to the limbs of the shell member, one of said limbs being provided with an extension constituting an arm, a contact piece on the arm defining a movable contact cooperable with the contact piece on the up standing part, said post extending through the passage of the heel member whereby the heel member is pivotally mounted on the contact plate, spring means connected to the heel member and the contact plate to urge the heel member to pivot relative to the plate to engage the contact piece on the arm with the contact piece on the upstanding part, and said cam follower being adapted to be engaged intermittently by lobes of a cam shaft of the distributor to pivot the heel member relative to the contact plate to move the movable contact into and out of engagement with the fixed contact. 

1. A contact breaker heel subassembly including an insulating heel member having a pair of oppositely directed shoulders thereon, and a conductive shell member engaged with the heel member, said shell member being of generally U-shaped cross section and said heel member being received between the limbs of said shell member, said shoulders of said heel member engaging opposite ends of said shell member and thereby resisting longitudinal movement of the shell member relative to the heel member and one of the limbs of said shell member including an integral protrusion which bites into one of said shoulders and thereby resists movement of the shell member relative to the heel member in a direction parallel to the limbs of the shell member.
 2. A contact breaker assembly for ignition distributors including a contact plate, an upstanding part on the plate, a contact piece on the upstanding part defining a fixed control a post on the plate in spaced relationship to the upstanding part, an insulating heel member, said heel member having at one end a pair of curved resilient arms forming therebetween a passage and at the other end a cam folLower portion, one of said arms defining with the heel member a first outwardly directed shoulder, said cam follower defining with said heel member a second outwardly directed shoulder, a generally U-shaped conductive shell member engaged with the heel member, with the heel member being received between the limbs of the shell member, said first and second shoulders engaging opposite ends of the shell member thereby resisting longitudinal movement of the shell member relative to the heel member, one of the limbs of the shell member having an integral protrusion which bites into one of said shoulders for resisting movement of the shell member relative to the heel member in a direction parallel to the limbs of the shell member, one of said limbs being provided with an extension constituting an arm, a contact piece on the arm defining a movable contact cooperable with the contact piece on the upstanding part, said post extending through the passage of the heel member whereby the heel member is pivotally mounted on the contact plate, spring means connected to the heel member and the contact plate to urge the heel member to pivot relative to the plate to engage the contact piece on the arm with the contact piece on the upstanding part, and said cam follower being adapted to be engaged intermittently by lobes of a cam shaft of the distributor to pivot the heel member relative to the contact plate to move the movable contact into and out of engagement with the fixed contact. 